Skin‐ny deeping: Uncovering immune cell behavior and function through imaging techniques*

Abstract

As the largest organ of the body, the skin is a key barrier tissue with specialized structures where ongoing immune surveillance is critical for protecting the body from external insults. The innate immune system acts as first‐responders in a coordinated manner to react to injury or infections, and recent developments in intravital imaging techniques have made it possible to delineate dynamic immune cell responses in a spatiotemporal manner. We review here key studies involved in understanding neutrophil, dendritic cell and macrophage behavior in skin and further discuss how this knowledge collectively highlights the importance of interactions and cellular functions in a systems biology manner. Furthermore, we will review emerging imaging technologies such as high‐content proteomic screening, spatial transcriptomics and three‐dimensional volumetric imaging and how these techniques can be integrated to provide a systems overview of the immune system that will further our current knowledge and lead to potential exciting discoveries in the upcoming decades.

Tetrahedral Framework Nucleic Acids Inhibit Skin Fibrosis via the Pyroptosis Pathway

“…The skin is the largest organ of the body and plays a crucial role as the first line of defense against a wide variety of endogenous and exogenous infectious agents and injuries. , Adverse events affect skin homeostasis and make the skin susceptible to the influence of multiple stimuli and toxins . When the intensity or duration of skin injury exceeds the ability of tissue repair, skin fibrosis resulting from a dysregulated tissue-repair response begins to dominate the repair process.…”

Biomechanical control of lymphatic vessel physiology and functions

“…Only low numbers of naive T cells are usually present in afferent lymph, and most of the T cells are antigen- experienced memory cells [ 40 , 41 ], although a significant proportion of CD4 + T cells are T regulatory cells, as recently demonstrated using photoconvertible Kaede mice [ 42 ]. Advances in in vivo and in vitro methods to assess cell migration, such as time-lapse imaging in tissue explants and intravital microscopy [ 43 , 44 ], have greatly contributed to elucidating the cellular and molecular mechanisms controlling lymphatic migration of DCs and T cells (as reviewed [ 43 , 45 , 46 ]). The chemokine receptor CCR7 expressed on the surface of DCs and its ligand CCL21 produced by lymphatic endothelial cells (LECs) [ 47 – 49 ] are the main molecules involved in DC migration via afferent lymphatics under steady-state and inflammatory conditions; CCR7 and CCL21 guide DCs through the interstitium toward afferent lymphatics and within the initial lymphatics toward collecting vessels [ 50 – 52 ].…”